Aside from being based on Fedora 39 now, KDE is now the official desktop environment replacing GNOME. The reasons why are in the article.
The GNOME version of Nobara still exists, but it’s going to be the vanilla version shipped without any extensions (probably because many of them broke after moving to Fedora 39)
Literally just install GNOME
As I understand it, that’s not even needed because the current DE choice is being preserved at an upgrade. The only thing that needs manual tweaking is reinstalling the extensions from the Gnome website which isn’t really an issue at all.